There is some problem with Gigabyte boards and SSD and Windows Boot Manager. I have a Gigabyte intel based gaming-5 series motherboard with 2 ssd disks, one is M.2 type 970 EVO Samsung series PCI-e interface disk and another is 840 series SATA Samsung SSD (with firmware upgraded!) and it:
- sometimes sees the same bootloader twice (in BIOS when you are choosing boot priority you are presented with the same boot manager listed twice)
- very often does not see one of the SSD disks (not presented in boot menu at all)
- often when you choose the correct windows bootloader from menu it still cannot boot (a message on black screen that the boot device does not contain correct boot sector)
- sometimes when I enter the boot menu (F12 key) I can correct it somehow but not from the main bios menu.
- I have once managed to boot properly when I have chosen the EMPTY slot in boot menu (from F12key menu)!!!!!!
- very often when 2 SSDs are present I cannot select the UEFI USB device to boot from (does not see appriopriate entry) but once I have managed to boot from UEFI USB device when I have chosen .... windows bootloader on one of the SSD disks from menu.
It seems like the information in BIOS menu is somehow random and does not reflect what the BIOS internally thinks, and the order of disks in menu is irrelevant to some internal bios structures and the choices on what to boot from are taken somewhere outside BIOS menu.
I wanted to achieve one simple goal:
- have Windows with windows boot manager on M.2 PCI-E type disk
- and have Linux on Samsung 840 series SATA SSD
And choose between t-hem from BIOS Boot menu not from the bootloader (I use linux very rarely so I dont want to confuse other users of the same machine).
And I failed. After 4 hours of battle I have manager (replace r to d in previous word please) to make windows boot problem free and gave up the linux thing.
Sorry for the '-' dash in t-hem word and for manager instead of manage-d but I was not able to write it correctly because it there is some silly autocorrection on tom's hardware site which is changing t hem to tchem and doing other silly things).